Detection and molecular characterization of tick-borne pathogens infecting sheep and goats in Blue Nile and West Kordofan states in Sudan

Abstract

Tick-borne pathogens (TBPs) are common in livestock of sub-Saharan Africa. However, information regarding TBPs in sheep and goats in Sudan is limited. In this study, 178 blood samples of sheep and goats in Blue Nile and West Kordofan states were investigated for TBPs using PCR. Overall, 110 (61.8%) samples were found to be infected with at least one of the following pathogens: Anaplasma ovis, Theileria ovis, and Ehrlichia ruminantium. Babesia ovis and T. lestoquardi were not identified. A. ovis was the most prevalent pathogen (n = 107, 60.1%), followed by T. ovis (n = 23, 12.9%) and E. ruminantium (n = 1, 0.6%). The prevalence rates of A. ovis and T. ovis were significantly higher in sheep than in goats. Phylogenetic analysis of T. ovis 18S rRNA and A. ovis msp4, groEL, and 16S rRNA, revealed that the pathogens identified in this study are clustered together, indicating similar molecular characteristics. Additionally, phylogenetic analysis of E. ruminantium pCS20 revealed that E. ruminantium in this study belong to the West Africa group, and different to E. ruminantium previously identified in ticks from Sudan. We concluded that TBPs are highly prevalent in the study area and continuous monitoring of TBPs in sheep and goats in Sudan is highly required.

Keywords: Anaplasma ovis; Ehrlichia ruminantium; Sudan; Theileria ovis; Tick-borne disease.